Unusual gastric tumors and tumor-like lesions: Radiological with pathological correlation and literature review.

Although gastric tumors have overlapping radiologic appearances, some unusual tumors may present specific imaging features. Using multidetector computed tomography (MDCT), with water as a negative oral contrast agent and intravenous contrast medium, can provide critical information for the diagnosis of gastric diseases. In addition, MDCT can evaluate the involvement of the gastric wall and extragastric extent of the disease, as compared with gastroenteroscopy and double-contrast upper gastrointestinal study. Regarding lesion location and size, enhancing and growth patterns, presence of calcification or fat, and involvement of the gastric wall and adjacent structures, CT may provide useful information. In this review article, we review the relevant literature and discuss the CT features and the histopathologic findings of different types of gastric lesions. The lesions are divided into benign (glomus tumors, schwannomas, leiomyomas, and lipomas), malignant (gastrointestinal stromal tumors, mucinous carcinomas, lymphomas, and carcinoid tumors), and tumor-like lesions (ectopic pancreas and bezoar). Familiarity with imaging appearances and pathologic findings can help physicians make an accurate diagnosis.

Hyaline-vascular variant of Castleman's disease mimicking a gastric submucosal tumor.

Castleman's disease is a rare lymphoproliferative disorder with unknown underlying cause. Three histologic variants (hyaline-vascular, plasma cell and mixed) as well as 2 clinical groups (localized and multicentic) have been described. Most patients with the hyaline-vascular variant are asymptomatic other than localized pressure from the mass. Hyaline-vascular Castleman's disease was commonly found as intrathoracic presentation. Extrathoracic lesions have been reported in the retroperitoneum, mesentery, central nervous system, orbit, pelvis, neck, axilla, and skeletal muscles. Herein, we report a case of hyaline-vascular Castleman's disease mimicking a gastric submucosal leiomyoma that has rarely been reported in English literature review. The lesion was not actually developing from the stomach, however, the clinical presentation was mimicking a submucosal gastric tumor. Furthermore, the patient in this case had both chronic hepatitis C and splenosis. The relationship between the underlying diseases and the development of the CD deserves further investigations.